Electrical heating unit, heating device for a vehicle and method for producing a heating unit

Abstract

An electrical heating unit for a heating device for a vehicle is provided comprising a heating layer and a heat conducting body. The heating layer may comprise at least one heating resistor, and the heat conducting body may comprise a heat absorbing face for absorbing heat from the heating layer and a heat releasing face for releasing heat to a heat carrier fluid. The heat conducting body may comprise a base body and at least two heat releasing bodies, wherein the base body and the heat releasing body may be connected to each other by substance bonding or integrally formed, wherein the heat absorbing face is a surface of the base body facing the heating layer and extending parallel to the heating layer, and the heat releasing face is a surface of the heat releasing bodies. A heating device and method for producing a heating unit is provided.

The invention claimed is: 
     
       1. An electrical heating unit for a heating device for a vehicle comprising a heating layer and a heat conducting body, wherein the heating layer comprises at least one heating resistor, and the heat conducting body comprises a heat absorbing face for absorbing heat from the heating layer and a heat releasing face for releasing heat to a heat carrier fluid, wherein the heat conducting body comprises a base body and at least two heat releasing bodies, wherein the base body and the heat releasing bodies are connected to each other by substance bonding or are integrally formed, wherein the heat absorbing face is a surface of the base body facing the heating layer and extending parallel to the heating layer, and the heat releasing face is a surface of the heat releasing bodies. 
     
     
       2. The heating unit according to  claim 1 , wherein the base body and the heating layer are connected to each other by substance bonding. 
     
     
       3. The heating unit according to  claim 1 , wherein an electrically insulating insulation layer is provided between the heating layer and the base body. 
     
     
       4. The heating unit according to  claim 3 , wherein the insulation layer contains a ceramic material or a polymer material. 
     
     
       5. The heating unit according to  claim 1 , wherein the heating unit comprises at least one plug-in device provided to engage with a complementary plug-in device of a second heating unit having the identical in construction. 
     
     
       6. The heating unit according to  claim 1 , wherein the heating layer is free of another heat conducting body on its side facing away from the heat absorbing face, and wherein no flow area for a heat carrier fluid is provided on the side of the heating layer facing away from the heat absorbing face either. 
     
     
       7. The heating unit according to  claim 1 , wherein the heat releasing face is larger than the heat absorbing face. 
     
     
       8. The heating unit according to  claim 1 , wherein the heat releasing bodies are formed as heat ribs. 
     
     
       9. The heating unit according to  claim 1 , wherein the heat releasing bodies extend in a plane perpendicular to the heat absorbing face. 
     
     
       10. A heating device for a vehicle comprising a heating unit according to  claim 1 . 
     
     
       11. The heating device according to  claim 10  comprising a stack of at least two heating units according to  claim 1 . 
     
     
       12. The heating device according to  claim 11  comprising a clamping device pressing the at least two heating units against each other. 
     
     
       13. A method for producing a heating unit according to  claim 3 , the method comprising the steps of:
 manufacturing the heat conducting body; 
 applying the insulation layer to the heat absorbing face; and 
 applying the heating layer to the insulation layer. 
 
     
     
       14. The method according to  claim 13 , wherein the step of applying the insulation layer to the heat absorbing face uses a plasma coating method. 
     
     
       15. The method according to  claim 13 , wherein the step of applying the heating layer to the insulation layer uses a plasma coating method, a screen printing method or a resistor paste. 
     
     
       16. The heating unit according to  claim 7 , wherein a heat conduction coefficient for a heat flow through the heat releasing face is lower than a corresponding heat conduction coefficient for a heat flow through the heat absorbing face. 
     
     
       17. The heating unit according to  claim 11 , wherein a first heating unit and a second heating unit of the at least two heating units are adjacent with respect to each other, wherein the first heating unit and the second heating unit share a common heat conducting body consisting of the heat conducting body of the first heating unit and the heat conducting body of the second heating unit, wherein the heat conducting bodies are connected to each other by substance bonding or integrally formed. 
     
     
       18. The heating unit according to  claim 3 , wherein the insulating layer has a thickness, and the thickness is less than 1 millimeter. 
     
     
       19. The heating unit according to  claim 3 , wherein the insulating layer has a thickness, and the thickness is in the range between 300 micrometers and 999 micrometers. 
     
     
       20. The heating unit according to  claim 1 , wherein the heat carrier fluid is a liquid. 
     
     
       21. The heating unit according to  claim 1 , wherein in operation of the heating unit, the heat carrier fluid flows past the heat releasing face. 
     
     
       22. The heating unit according to  claim 1 , wherein the heat conducting body is formed of metal.